Method for dyeing polyesters



United States Patent 3,246,945 METHOD FOR DYEING POLYESTER Lester N. Stanley, Delmar, William H. Armento, Albany,

and William G. Huey, Nassau, N.Y., assignors to General Aniline & Film Corporation, New York, N.Y., a corporation of Delaware No Drawing. Filed Oct. 10, 1963, Ser. No. 315,361 22 Claims. (Cl. 8-41) The present invention relates to a method for dyeing polyester fibers and more specifically to a method for dyeing polyester fibers with particular water-insoluble monoazo dyestuffs formed by coupling a diazotized 4'-amino-benzanilide with a pyrazolone.

As is well known, polyester fibers such as those formed of polymeric reaction products of terephthalic acid and polyhydric alcohols have little or no afiinity for dyestuffs normally employed for dyeing natural fibers. Furthermore, most dyestuils proposed for utilization in dyeing such polyesters are not completely suitable in providing dyed articles displaying excellent sublimation and crocking properties, color fastness to light, heat, gases, dry cleaning, alkali, perspiration and similar agents encountered in the normal use, wear, handling and/or washing of the dyed articles.

Thus, it is recognized that a need exists for providing dyestuffs which are characterized by an ability to satisfactorily dye polyester fibers which are stable and which broaden the color range of suitable dyes available to the dye consumer.

Accordingly, it is the primary object of the present invention to provide a method for dyeing polyesters which provides colored articles having excellent color stability.

It is another object of the present invention to provide a method for dyeing a polyester fiber to a yellow to orange color to provide a colored article which advantageously displays excellent color fastness when subjected to the conditions ordinarily encountered in the dyeing use, wear, handling and washing of the colored article.

It is a particular object of the present invention to provide a method for dyeing a polyester fiber wherein a yellow to orange color is imparted to the fiber of excellent sublimation properties, and excellent strength and fastness to light, heat, water, alkali, and the like agents ordinarily encountered in the dyeing use, wear, handling, and/or washing of the dyed fibers.

Broadly described, the present invention provides a method for dyeing a textile material which comprises contacting said textile material with a dye bath containing a monoazo dyestuff having the general formula wherein R is selected from the group consisting of hydrogen, alkyl having from 1 to 6 carbon atoms, cycloalkyl having from 3 to about 6 carbon atoms, aryl having no more than 2 benzene nuclei, and monovalent substituted radicals consisting of said alkyl, cycloalkyl, and aryl radicals containing substituents selected from the group consisting of halo, nitro, lower alkyl, lower alkoxy, sulfamyl, lower alkyl mono and disubstituted sulfamyl, and heterocyclic substituted sulfamyl, i.e., N-morpholinosulfamyl, N-piperidinosulfamyl, and the like groups; R is selected from the group consisting of hydrogen, lower alkyl, carboxy, lower carbalkoxy, carbamyl, and lower alkyl substituted carbamyl; and each of X and Y is selected from the group consisting of hydrogen, halo, nitro, lower alkyl, and lower alkoxy.

The monoazo dyestuffs employed in the method of the invention are prepared by diazotizing a 4'-amino-benzanilide of the formula wherein and Y have the meaning indicated hereinabove, and coupling the corresponding diazotized aromatic amine with a pyrazolone of the formula wherein R and R are as defined above. The diazotization and coupling reactions suitably may be carried out according to any of the well-known conventional techniques.

Specific examples of suitable 4'-amino-benzanilides employed in preparing the monoazo dyestuifs utilized in the present method include, without limitation,

4'-aminobenzanilide 4-amino-2'-chloro-benzanilide 4'-amino-2'-bromo-benzanilide 4'-amino-2-iodo-benzanilide 4'-amino-3 '-chloro-benzanilide 4'-amino-2',5-dichloro-benzanilide 4-amino-2,5'-dibromo-benzanilide 4'-amino-2',6-dichloro-benzanilide 4-amino-3',5'-dichloro-benzanilide 4'-amino-2'-chloro- 5 '-methyl-benzanil-ide 4'-amino-2'-chloro-5 '-methoxy-benzanilide 4-amino-2'-chloro-5 '-nitro-benzanilide 4'-amino-2'-chloro-6'-methyl-benzanilide 4'-amino-2-chloro-6-ethoxy-benzanilide 4'-amino-2,3'-dichloro-5'-methyl-benzanilide 4'-amino-3-chloro-5'-methoxy-benzanilide 4-arnino-3 '-chloro-5'-nitro-benzanilide 4'-amino-3'-bromo-6-ethyl-benzanilide 4'-amino-3 -brorno-6'-ethoxv-benzanilide 4-amino-3 '-bromo-6-nitro-benzanilide 4-amino-3'-chloro-6'-butyl-benzanilide 4'-arnino-5 '-chloro-2'-methyl-benzanilide 4'-amino-5'-chloro-2'-ethoxy-benzanilide 4-amino-5 -chloro-2'-nitro-benzanilide 4'-amino-5'-chloro-3-methyl-benzanilide 4'-amino-5'-bromo-3'-nitro-benzanilide 4-amino-6'-chloro-2'-ethyl-benzanilide 4'-arnino-6'-chloro-2'-methoxy-benzanilide 4'-amino-6'-chloro-2'-nitro-benzanilide 4'-amino-6'-chloro-2'-propyl-benzanilide 4'-amino-6'-bromo-3-methyl-benzanilide 4-arnino-6'-bromo-3'-ethoxy-benzanilide 4'-amino-2'-nitro-benzanilide 4'-amino-3'-nitro-benzanilide 4-amino-3',6'-dinitro-benzanilide 4-amino-3,5'-dinitro-benzanilide 4-amino-5 '-methyl-2'-nitro-benzanilide 4'-amino-2-nitro-5'-propyl-benzanilide 4'-amino-6'-ethyl-2'-nitro-benzanilide 4'-amino-6'-butyl-2'-nitro-benzanilide 4-amino-6'-methoxy-2'-nitro-benzanilide 4-amino-6'-butoxy-2'-nitro-benzanilide 4'-amino-5-methyl-3 -nitro-benzanilide 4-amino-5'-methoxy-3'-nitro-benzanilide 4'-amino-6-ethyl-3'-nitro-benzanilide 4'-amino-6'-methoxy-3'-nitro-benzanilide Patented Apr. 19, 1966 .5 tion and dyeing in pressurized machines at a temperature up to about 125 C.

A preferred method of dyeing the fiber with the dyestulf is by means of the Thermosol process wherein the fiber is padded with a dispersion of the dyestuif, dried and subjected to a temperature of 190 to 230 C. for about /2 to 1 minute. It is in the exercise of this method of dyeing that sublimation fastness is very important, and the fact that the instant dyes have excellent sublimation fastness accounts for their value.

The method of the invention contemplates the utilization of any surface-active agent conventionally employed for providing dyestuff and/ or dyestuff-carrier dispersions for dyeing polyesters. Such surface-active agents generally are nonionic, anionic or mixtures thereof. Specific examples of such surface-active agents include watersoluble ligninsulfonates, i.e., the sodium, calcium, and magnesium salts of ligninsulfonic acids and partly disulfonated ligninsulfonic acids such as those disclosed in US. Patent No. 2,371,136; alkyl naphthalene sulfonates, e.g., the sodium, potassium, and ammonium salts of monoand dipropyl and butyl-naphthalene sulfonates; alkali metal fatty sulfates, such as sodium lauryl sulfate, sodium tridecyl sulfate and sodium tallow sulfate; alkali metal salts of alkyl sulfosuccinates, such as sodium dioctyl sulfosuccinate; alkali metal alkyl aryl sulfates, such as sodium nonyl benzene sulfate; ethylene oxide ethers of alkyl phenols, such as nonylphenol polyoxyethylene ethers; ethylene oxide ethers of fatty alcohols, such as tridecyl alcohol polyoxyethylene ethers; ethylene oxide ethers of alkyl mercaptans, such as dodecyl mercaptan polyoxyethylene thioethers; ethylene oxide esters of fatty acids, such as the condensation products of lauric acid and polyethylene glycols; ethylene oxide condensation products of fatty amides, such as lauramide; and condensation products of ethylene oxide with partial fatty acid esters of polyhydric alcohols, such as the lauric acid esters of sorbitol polyethylene glycol ethers; and the like.

In accordance with the method of dyeing polyester fiber with the instant dyes, a wide range of temperatures may be utilized. When ordinary dyeing methods at atmos pheric pressure are employed, temperatures above room temperature are usually employed ranging from about 80 C. to the boil. Better results are obtained when dyeing is carried out at high temperatures such as would prevail in a pressure vessel. In dyeing in a pressure vessel, temperatures up to about 125 C. are employed. Still better results are obtained when the Thermosol process is employed wherein the workable temperature range is 190 to 230 C., best results being obtained at the 210 to 220 C. range.

The amount of the dyestuff employed in the dyebath in accordance with the present invention may vary widely. The amount usually employed in embodiments of the inventionwherein the dyeing is effected by immersing the fabric into hot dyebath is in the range of from about 0.01 to about 15 parts by weight, preferably 0.1 to about parts by weight, per 100 parts water in the dyebath. In embodiments of the invention wherein the Thermosol dyeing technique is employed, greater proportions of dyestuif to water suitably may be employed, the dyebath utilized being in the form of a dispersion of the dyestutf.

The contacting of the present method is carried out over a time period requisite to provide the desired build-up of dyestutf, as evidenced by the color depth of the dyed article to be obtained. At the above-indicated preferred temperatures and dye concentrations, the time periods normally required are in the range of from a few minutes to about 3 hours.

It is understood that the actual temperature and time period employed in a given embodiment of the invention will vary depending upon, inter alia, the dyeing technique employed, the particular nature and amounts of polyesters and dyestuff employed, and the desired color depth of the final dyed product as well as the particular carrier and surface-active agent, if any, utilized.

Following the contacting step, the dyed article suitably may be rinsed and dried in any conventional manner.

The present method contemplates dyeing polyesters broadly. The particular polyesters most commonly utilized are the polyesters of terephthalic acid and aliphatic and aromatic polyhydric alcohols, e.g., ethylene glycol, propylene glycol, glycerine, p-xylene glycol and the like.

The method of the invention having been described above in detail, the following examples are presented to show specific embodiments thereof. It will be understood that the examples are given merely for illustration purposes and not by way of limitation.

Example 1 36.8 g. of 4'-aminobenzanilide (0.174 mol) in the form of the HQ salt and 30 cc. of 20 B. hydrochloric acid were mixed with 440 cc. of water. At a temperature of 15 C., 34 cc. of sodium nitrite solution (38.5% by vol.) was added slowly to the mixture over a period of about 4 hours to form the corresponding diazotized compound. The diazo-c-ontaining solution was then treated with activated carbon and filtered. Excess nitrite in the filtrate was destroyed by a treatment with sulfamic acid. 30.2 g. of 3-methyl-l-phenyl-S-pyrazolone was dissolved in 500 cc. of water also containing 20 g. of soda ash and 20 g. of sodium bicarbonate. The diazo solution was then combined with the pyrazolone coupler solution by running it into the coupler solution below 15 C., while maintaining the pH between 8 and 8.5. After stirring for one hour, the pH was adjusted to slight phenolphthalein alkalinity with sodium hydroxide, the resulting yellow dyestuff precipitate was filtered, Washed with water and dried. The dyestutf obtained had the formula HO-C B T A dyebath of the above-described dyestutf was formed by initially mixing about '1 cc. of a 10% solution of Avitone T, a sodium hydrocarbon sulfonate, with stirring into cc. of water at 54 C. About 20 cc. of each of a 10% solution of diammonium phosphate and a 10% solutionof sodium phenyl phenolate were then introduced with stirring into the resulting mixture. A dispersion of about 1 g. of the dyestuff pasted in 10 cc. of a 10% solution of Avit-one T was then mixed with the phosphate-containmg mixture and the resultant mixture was then diluted with water to 300 cc.

A sample of polyglycol terephtha-late (Dacron) fabric was then immersed in the dyebath, and the dyebath was heated to boiling. The fabric was maintain-ed in the boilmg dyebath for about 1 hour. At the end of this period the fabric was removed from the dyebath, immersed in a bOlllIlg 0.1% soap solution for about 5 minutes, thereafter rinsed with water, and then dried.

The dyeing thereby obtained had a bright, strong, yellow color and the dyed fabric displayed excellent sublimation properties, excellent fastness to heat, light, washing and crocking.

Example 2 The procedure of Example 1 was repeated with the exception of substituting 40.4 g. of 3-carbethoxy-1-phenyl- S-pyrazolone for the 3-methyl-1-phenyl-5-pyrazolone. An orange-yellow dyestuif was obtained having the formula A dyebath of the above-described dyestuff was prepared and a sample of Dacron fabric dyed therewith in accordance with the procedure of Example 1.

The dyed fabric obtained had a bright, strong, orangeyellow color and was characterized by excellent sublimation properties and excellent fastness to light, heat, washing, and crocking.

Example 3 18 g. of S-methyl-S-pyrazolone was dissolved in 400 cc. of water containing 20 g. of soda ash and 20 g. of sodium bicarbonate to form a coupler solution. A diazo solution was prepared in the same manner as in Example 1 and was combined at 15 C. with the coupler solut-i-on. After standing overnight, the pH of the resulting mixture was adjusted to slight phenolphthalein alkalinity and the yellow dyestuff precipitate formed was filtered, washed with water and dried. The dyestuif thereby obtained had the formula Example 4 A dyebath of the above-described dyestulf was prepared and a sample of Dacron fabric dyed therewith in accordance with the procedure of Example 1.

The dyed fabric thereby obtained was observed to have excellent sublimation characteristics and to display fastness to heat, light, washing and crocking.

Example 5 21.3 g. of l-(2,5'-dichlorophenyl)-3-me-thyl-5-pyraz0- lone was dissolved in 250 cc. of water containing g. of soda ash and 10 g. of sodium bicarbonate to prepare a couplersolution; 'One-half'of a diazo solution produced 8 as in Example 1 was combined with this coupler solution at below 15 C. After stirring one hour, the pH of the resulting mixture was adjusted to slight phenolphthalein alkalinity and the dyestuff precipitate formed was filtered, washed and dried. The dyestuff obtained had the formula A dyebath of the above-described dyestuff was prepared and a sample of Dacron. fabric dyed therewith in accordance with the procedure of Example 1.

The dyed fabric thereby obtained was observed to have excellent sublimation characteristics and to display fastness to heat, light, washing and cro'cking.

Example 6 18 .g. of 3-carbethoxy-5-pyrazolone was dissolved in 250 cc. of water containing 10 g. of soda ash and 10 g. of sodium bicarbonate to prepare a coupler solution. One-half of a diazo solution produced as in Example 1 was combined with this coupler solution at below 15 C. After stirring one hour, the .pH of the mixture was adjusted to slight phenolphthalein alkalinity, the resulting dyestuff then being filtered, washed and dried. The dyestuif obtained had the formula A dyebath of the above-described dyestuif was prepared and a sample of Dacron fabric dyed therewith in accordance with the procedure of Example 1.

The dyed fabric thereby obtained was observed to have excellent sublimation characteristics and to display fastness to heat, light, washing and crocking.

Example 7 27 g. of 4' amino 2',5 dirnethoxybenzanilide was stirred with a mixture of 220 cc. of water and 25 cc. of hydrochloric acid. At a temperature of 15 'C., 19 cc. of sodium nitrite solution (38.5% by vol.) was added slowly to the resulting mixture over a period of about 2 hours. The nitrite-containing mixture was then treated with activated carbon which subsequently was removed by filtration. Excess nitrite in the filtrate was destroyed by treatment with sulfamic acid. The resulting diazo solution, at below 15 C., was run into a coupler solution which consisted of'9.8 g. of 3-methyl-5-pyrazolone dissolved in a solution of 10.5 g. of soda ash and 11 g. of sodium bicarbonate in 250 cc. of water. The pH of the mixture was then adjusted to slight phenolphthalein alkalinity and after stirring overnight the dyestutf precipitate formed was filtered, washed with water and dried. The dyestulf obtained had the formula A dyebath of the above-described dyestuif was prepared and a sample of Dacron fabric dyed therewith in accordance with the procedure of Example 1.

. l -C N t Example 8 A diazo solution was produced as in Example 7 with the exception that 30 g. of 4-ami no-2,5-diethoxybenzanilide was substituted for 4'-amino-2',5'-dimethoxybenzanilide. This diazo solution was added to a coupler solution which consisted of 23.2 g. of B-carbethoxy-l-phenyl- 5-pyrazolone dissolved'in a solution of g. of soda ash and 10 g. of sodium bicarbonate in 250 cc. of water. At C. the diazo solution was run into the coupler solution 'while keeping the pH thereof adjusted to slight phenolphthalein-alkalinity. After stirring the resulting mixture overnight, the dyestulf precipitate formed was filtered, washed and dried. The dyestuff thereby obtained had the formula excellent sublimation characteristics and to display fast- W ness to heat, light, washing and crocking.

I Example 9 A diazo. solution was produced as in- Example .7 with the exception that 25.6 g. of 4-amino-6f-methylbenz-manisidide was substituted for the 4'-amino-2',5-dimethoxybenzanilide. This diazo solution, at 15 C., was combined at a pH of 8 to 8.5 with a coupler solution consisting of 9.8 g. of 3-methyl-5-pyrazolone dissolved in a solution of 10.5 g. of soda ash and 11 g. of sodium bicarbonate in 250 cc. of water. After stirring the resulting mixture overnight, the pH thereof was adjusted to slightphenolphthaleinalkalinity, and the dye formed was filtered washed and dried. The dyestulf obtained had the formula r HO OCH;

A dyebath of the above-described dyestuif was prepared and a sample of Dacron fabric dyed therewith in accordance with the procedure of Example 1.

The dyed fabric thereby obtained was observed to have "excellent sublimation characteristics and to display fast- .exception that.28 g. of 4'-amino-6 '-chlorobenz-m-anisidide was substituted for the 4'-amino-2',5'-dimethoxy- .benzanilide. This diazo solution, at 15". C. and while maintaining a pH of 8 to 8.5, was run into a coupler solution consisting of 22.9.g. of 1-(5'-chloro-o-anisyl)-3-methyl-5-pyrazolone dissolved in 250cc. of water also containing" 10 g. of soda ash and -10. g. of sodium bicarbonate. After stirring the resulting mixture overnight, thepH thereof was adjusted to "slightphenolphthalein alkalinity, and the dyestulf precipitate formed was filtered, washed and dried. The dyestulf thereby obtained had the formula Cl I HO-O N OCH;

A dyebath of the above-described dyestulf was prepared and a sample of Dacron fabric dyed therewith in accordance with the procedure of Example 1.

The dyed fabric thereby obtained was observed to have excellent sublimation characteristics and to display fastness to heat, light, washing and crocking.

Example 11 One-half of a diazo solutionproduced as in Example 1 was combined with a coupler solution which consisted of 24.8 g. of 1-(3'-nitrophenyl)-5-pyrazolone-3-yl carboxylic acid in a solution of 10.5 g. of soda ash and 11 g. of sodium bicarbonate in 250 cc. of water. After the resulting mixture was stirred overnight, the pH thereof was adjusted to slight phenolphthalein alkalinity, and the dyestuff obtained was filtered, Washed and dried. The resultant dyestufi .had the formula N a p A dyebath of the above-described dyestutf was prepared and a sample of Dacron fabric dyed therewith in accordance with the procedure of Example 1.

The dyed fabric thereby obtained'was observed to have excellent sublimation characteristics.

I Example 12 i A diazo solution produced as in Example 1 'was stirred into a coupler solution which consisted of 33 g. of 3- methyl-l-(p-tolyl)-5-pyrazolone dissolved in 500 cc. of water also containing-20 g; of soda ash and 20 g. of sodium bicarbonate while maintaining the temperature below 15 C. and the pH between 8 and 8.5. After the resulting mixture was stirred for one hour, the pH thereof was adjusted to slight phenolphthalein alkalinity with sodium hydroxide, and the dyestutf precipitate formed was filtered, washed with water, and dried. The dyestuff obtained had the formula I H0-o N v CH3 A dyebath of the above-described dyestufi was prepared and a sample of Dacron fabric dyed therewith in accordance'with the procedure of Example 1.

The dyed fabric thereby obtained was observed to have excellent sublimation characteristics and to display fast- 'ness to heat, light, washing and c'rocking.

'alkyl naphthalene sulfonate.

1.1 Example 13 A diazo solution produced as in Example 1 was stirred into a coupler solution which consisted of 35.2 g. of 3-carbamyl-1-phenyl-5-pyrazolone dissolved in 500 cc. of water containing 20 g. of soda.. ash and 20 g. of sodium bicarbonatewhilemaintaining the temperature below 15 C. and the pH between 8 and 8.5. After stirring the resulting mixture for one hour, the pH thereof was adjusted to slight phenolphthalein alkalinity with sodium hydroxide, and the dyestuff precipitate formed was filtered, washed with water and dried. The dyestutf obtained had the formula A dyebath of the above-described dyestuff 'was prepared and a sample of.Dacron fabric dyed therewith inaccordance With the procedure of- Example 1.

The dyed fabric thereby obtained was. observed to have excellent sublimation characteristics and to display fastness to heat, light, washing and-crocking.

Example 14 22 g. of the dyestutf of Example 2, 20 g. of Polyfon H, a sodium ligninsulfonate, and. 4 cc. of Nekal WS-ZS, a sodiumalkyl-naphthalene sulfonate,.were-wet down in a mixer with water to give a thick, doughy mess. The water was evaporated oil? to yield viscous mixture, and the resultant mixture was viscous milled for 1 hours, with water being added as needed. The dispersed dyestuff thereby obtained was then dried.

2 ounces of the dispersed dyestuif product was dispersed'in 83 cc. of warm water and poured into an aqueous solution containing 0.2 g. of Keltex gum, an alginic thickening'agent, and 1 cc. of Nekal'NF, a sodium The resultant solution was diluted up to a gallon with water. A Dacron fabric was padded at about 70 0., dried, and cured at about 220 C. for 90 seconds. The dyed material was then soaped at the boiling point for 5 minutes, washed and dried. A bright, strong, orange-yellow dyeing wasobtained which had excellent sublimation, wash and crock fastness properties and good fastnessv to light.

Example 15 A diazo solution produced as in Example 1 was stirred into a coupler solutionwhich consisted of' 49 grams of A polyester (Dacron) fabric was dyed with the abovedescribed dyestuff in accordance with the procedure of Example 14. During the dyeing the sublimation fast- 12 ness was excellent. The dyed fabric was a bright, clear yellow, having excellent fastness to light, washing and crocking.

While the above examples are limited to dyeing of polyesters, it will be understood that the present method also is applicable to the dyeing of textile'materials formed of natural materials, such as cotton, wool, and the like, and other synthetic fibers such as those formed of polyamides, polyvinyl compounds, cellulose acetate, viscose and the like.

Fromthe above description and examples various modifications will be apparent to those skilled in the art Which do not depart from the scope of the process of the invention. Thus it is intended that the invention be limited only by the scope of the appended claims.

What is claimed is:

1. A method for dyeing a polyester textile material which comprises contacting said textile material with a dye bath containing a monoazo dyestuif having the general formula wherein R is selected from the group consisting of hydrogen, alkyl having from 1 too carbon atoms, cycloalkyl having from 3 to about 6 carbon atoms, aryl having no more than 2 benzene nuolei,and' mono-valent substituted radicals consisting of said a lkyl; cycloalkyl, and aryl radicals containing substituents selected from the group consisting of halo, nitro, lower alkyl, lower al'koxy, sulfamyl, and substituted sultamyl groups; R is selected from the group consisting of hydrogen, lower alkyl, canboxyl, lower oarbalkoxy, carbamyl, and lower alkyl substituted carbarnyl; and each X and Y is selected from the group consisting of hydrogen, halo, nitro, lower alkyl, and lower alkoxy.

2. The method according to claim 1 wherein said dye bat-h contains a dyestuif'oarrier' and a surface-active agent as a dispersing agent.

3. The method according t'ct' claim 2 wherein said dyestutf carrieris selected from the group consisting of methyl salicylate and o phenylphenol, and said surfaceactive agent is selected from the group consisting of anionic surface active agents, nonionic surface active agents, and mixtures thereof.

4. The method according to claim 1 wherein said contactingis carried out by immersing said textile material into said dyebath at a temperature in the range of from about to about C.

5. The method according to claim 1 wherein said dyebath is in-the form of a dispersion of said dyestuff, and subsequent to said contacting of said textile material with said dyestulf dispersion, the resultant dyestulf dispersion-containing textile material is dried, and thereafter heated at a temperature in the rangeof from about to about 230 C.

6. The method according 'to claim 1 wherein! the amount of said dyestutf in said dyebath is in the range of 0.01 to about 15 parts by weight per 100parts water in said bath.

7. The method according to claim 1 wherein X and Y are hydrogen, R is phenyl, and R is lower alkyl.

8. The method according to claim 1 wherein X and Y are hydrogen, R isphenyl, and R is lower carbalkoxy.

9. The method according to claim 1 wherein X and Y are hydrogen, R is hydrogen, and R is lower alkyl.

t 13 l V t a 14 r 10. The method according to claim 1 wherein said 16. The method according to claim 1 wherein said dyestuif has the formula dyestulf has the formula v i V r 7 OCH! I g HO O N OCONH N=N(fi(l'l)-CH,

- HOC N OCH:

17. The method according to claim 1, wherein said dyestufi has the formula 11. The method according to claim 1 wherein said 0023:

15 dyestuff has the formula 12. Th th d ccord'n to claim 1 wherein said dyestuff lias fhe for r nula l g 18. The method according to claim 1 wherein said 19. The method according to claim 1 wherein said dyestuff has the formula.

13. The method according to claim 1 wherein said dyestuff has the formula. 40 01 ll II N N OCH 20. A method according to claim 1 wherein said dyestuff has the formula 14. The method according to claim 1 wherein said dyestuff has the formula C -o 0NHC N=N(fi(1-COOH HO-C N N NO:

21. The method according to claim 1 wherein said 01 dyestutf has the formula CON-H --CCCH 15. The method according to claim 1 wherein said O N H u 3 HOC\ N dyestuif has the formula 22. The mcthod according to ql-aiml wherein said dyestufi hasthe formula.

7 References Cited by the Examiner UNITED STATES PATENTS Kruckenbe rg 841 Landerl 1855 :Rohland et-al. 260-162 Eltonhead 260-462 Bertie et a1. 8-41 Assistant Examiners. 

1. A METHOD FOR DYEING A POLYESTER TEXTILE MATERIAL WHICH COMPRISES CONTACTING SAID TEXTILE MATERIAL WITH A DYE BATH CONTAINING A MONOAZO DYESTUFF HAVING THE GENERAL FORMULA 